Resolved questionss'en falloir & il s'en est fallu de peu pour que

What does this phrase actually mean? Is it 'to come close to (being) something'? As I have only seen it being used in the third person singular, I wonder whether it can also be used in other persons. For example, if I want to say 'I have come close to knowing it,' do I say 'J'en suis fallu de peu pour que je le sache?